/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: WHY
 * Date: 2022-10-09
 * Time: 11:06
 */
public class Test {
    static void operate(StringBuilder x, StringBuilder y){

        x.append(y);

        y = x;

    }

    public static void main(String[] args){

        StringBuilder a = new StringBuilder ("A");

        StringBuilder b = new StringBuilder ("B");

        operate(a,b);

        System.out.println(a+","+b);
        String s = new String();

        System.out.println(s.length());



    }
}
